These are my own personal, current story structure theories. I do not claim them as the intentions of the filmmakers.

Cheers :-)

Close Encounters is a classic.
Written and directed by Steven Spielberg. There were four uncredited writers: Hal Barwood, Jerry Belson, John Hill, and Matthew Robbins.

Close Encounters of the Third Kind IMDb: https://m.imdb.com/title/tt0075860/

What you might call the inciting incident here is a bit blurry, as the entire opening sequence kicks off the story before there is much set up, before much backstory hits.

We see a series of government or UFO events, then meet our main character Roy with his family.

Roy soon has a close encounter with a UFO which affects him mentally and/or spiritually.

Act 1 wraps up between Roy chasing after the UFO's and him bringing his family to the bluff to look for them.
Ronnie: "What flavor?"
Roy: "Orange."

They stand and kiss, and we have a great moment of eye contact, and lack of eye contact, which sets up the emotional or personal conflict for the remainder of the film: a sort of radical exploration vs normalcy.

The radical exploration, the mystery, the journey is pinned right up against this normalcy again clearly at the midpoint of the film as Roy unravels and drives away his family in front of a jaw-dropped suburban neighborhood.

Roy is alone now. He realizes his visions are of Devils Tower and decides he must go there.

Journey, journey, journey.
Run into the military.
We have a great scene with François Truffaut.
Roy: "If this is just nerve gas, how come I know everything in such detail? I've never been here before. How come I know so much? What the hell is going on around here? Who the hell are you people?"

Journey, journey, journey.
We make it to Devils Tower.

Act 3 is probably the clearest story point transition in the film, starting when we cross to the other side of Devils Tower.

The questions of Act 1 and 2 are answered, and now we can ask new questions or at least go deeper into our questions.

We observe and melt into the spectacle of contact, of lights, of UFOs, and keyboard glow.
We even get to hang with Dr. J. Allen Hynek for a moment.

Roy goes further as we see radical exploration clearly take way for him over normalcy in the end, something we have been primed for since we first met him.

We join the ship.
We fly off into the next step of mankind's eternal journey.

Close Encounters of the Third Kind Trailer: 

Be well.

LionSuit.com
(words and image are original. posts may also be shown on my hive.blog page.)